datecode - prints out string YYYYMMDD where it is the Universal time date for the night to the closest midnight. In other words it changes to the next day at noon and lasts till the next noon.
iso - printout time and date in
ISO8601 format.
for example: 2007-01-25T00:00:16Z
The high option prints out milliseconds, otherwise it is just to
the nearest second.
iso= sets time and date in ISO8601 format rather than system clock.
jd= sets time and date to Julian date rather than system clock.
midnight - moves the clock to the next local midnight.
mday -prints out date string like Feb09 or Mar12.
unix - prints out the UNIX timestamp in seconds since 1970.
year=yyyy.yy - calculates for decimal year.
until= if specified as an ISO time, the number of seconds until that time occurs is printed out.
dut - prints out DUT, the difference from universal time in seconds.
all - prints out the ΔUT , x, and y values of the Earth Rotation parameters too.